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Old 22-06-2009, 08:17   #16
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All this talk fired me up to finally re-install my ham radio.... I am quite rusty at this and I did not have a backstay antenna on my previous boat installation - what is the recommended min/max length for -primarily- use with maritime mobile?

Also, during the counterpoise discussion, there was mention of adding a capacitor to block DC - I have a cast iron keel; seems as if this ought to be suitable for a good ground?.. What type of capacitor are we talking about and would someone describe the connection (perhaps a simple diagram?)

Thanks in advance and fair winds to all!

Sailndive
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Old 22-06-2009, 10:21   #17
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Quote:
Originally Posted by Sailndive345 View Post
... Also, during the counterpoise discussion, there was mention of adding a capacitor to block DC - I have a cast iron keel; seems as if this ought to be suitable for a good ground?.. What type of capacitor are we talking about and would someone describe the connection (perhaps a simple diagram?)...
Capacitors for use to block DC in SSB grounding tape:
Digi-Key, (800) 344 4539.
Type X7R Monolithic Ceramic capacitor, 0.15uF, $0.91 each,
Digi-Key part number P4911-ND.


See Stan Honey’s excellent article on “Marine Grounding Systems”; specifically “Inconsistencies in the Ground Rules”
Goto Grounding

"... Fasten the RF ground tape securely to an insulating piece of phenolic or to a terminal strip, cut a 1/10-inch gap across the tape, and solder several 0.15uF ceramic capacitors across the gap. These capacitors will be transparent to the RF, which will be happily grounded by the ground tape system, but they will block any DC currents from running through the RF ground system, and will avoid any resulting susceptibility to hot marina electrolytic corrosion..."

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